I've got four first year Centennials growing very well. I picked off a cone or two for a friend to smell. The cones unmolested smelled very oniony similar to CTZ. But after doing the "Jim Koch" rub they were much more centennial like. Is that normal for most fresh hops or just this variety?

In my experience, it is variety dependent.
My Nugget and Zeus (both a few weeks to harvest still) smell like hoppy goodness just by walking within 8-10ft of the bines. My Hallertau and Mt Hood I have to rub cones to get any distinctive hop smell.